Epitaxial lead titanate (PbTiO<sub>3</sub>) thin films on SrTiO<sub>3</sub> (100) substrate were grown <i>in situ</i> by radio-frequency sputtering for optical waveguiding applications. The crystalline quality of the PbTiO<sub>3</sub> films deposited at 550° C has been investigated through x-ray diffraction analysis. It indicates that thin films are completely <i>c</i>-axis oriented (rocking curve FWHM of 0.2° for the 001 reflection). The transmission spectrum method has been used to measure the dispersion of the refractive index. At 632.8 nm, the PbTiO<sub>3</sub> film with an (001) orientation exhibits a refractive index of 2.61, which represents 98% of the bulk material. The prism-coupling technique has been also employed to determine the optical attenuation in the planar waveguide. In this study, we report a low propagation loss of 2.2 ∓ 0.2 dB/cm obtained in a PbTiO<sub>3</sub> optical waveguide.
© 1998 Optical Society of America
Elhadj Dogheche, Boujemaa Jaber, and Dénis Rémiens, "Optical waveguiding in epitaxial PbTiO3 thin films," Appl. Opt. 37, 4245-4248 (1998)